Method of packaging live lobsters



April 13, 1943. MacDQNALD I 2,316,607

' METHOD OF PACKAGING LIVE LOBSTERS Filed Aug. 31. 1939 I OOOOOOOOOOO Jos p 1 3 M Patented Apr. 13, 1943 UNITED STATES PATENT OFFICE METHOD OF PACKAGING LIVE LOBSTERS Joseph R. Maodonald, Winchester, Mass.

Application August 31, 1939, Serial No. 292,847

4 Claims.

The present invention relates toa method of packaging live lobsters and keeping them alive for a considerable period of time, during storage or shipment.

It is well known that lobsters, after being caught, are usually kept for some time upon ice.

But they do not survive more than a day or two,

number of lobsters may be kept and transported,

conveniently and safely. Other objects 'will appear from the following: disclosure.

By the present invention it is found that if the freshly caught, live lobster is put into a'container, in a sufficient amount of water to cover the lobster, preferably while oxygen is being passed through the water, and a cover is then put on which is capable of hermetically sealing the can, the lobster maythereby be keptalive many days. The introduction of oxygen may be discontinued after the concentration of oxygen added, togetherwith the oxygen of the air left in the container is substantially increased but preferably after the air has been completely displaced. Or it may be continued gradually and uniformly, until a pressure is developed-in 'the container, which mayultim'ately' be substantially equivalent to that under which the lobster normally lives. dition of oxygen has beenfmade it is then shut off and the container closed so as to maintain such condition or pressure e. g., 3 to pounds per square inch above atmospheric pressure), and the lobster willlive'in the .closed container for many days or evenweeks. Moreoven'the lobster will not only be alive and healthy, but livelier and more healthy than when put in.

Several typical examples of the practical application of the invention, with different kinds of containers, will be described, with reference to the accompanying drawingin which:

Fig. 1 is a side view, with a portion broken away, of a cardboard carton wane metal bottom and friction-seal metal cover; Y Fig. 2 is a perspective view of an all-metal can, having a friction-seal metal cover;

.Fig. 3 is an enlarged radial cross-section of a portion of the top edge and cover of the can in Fig. 2;

In either case, when a suitable adaway, of a lobster as packed in a transparent Cellophane container;

Fig. 6 is a diametrical cross-section of the valve on the container in Fig. 5 along the line 6---6;

Fig. 7 is a cross=section of the rolled edgeseam of the container in Fig. 5 along the line 1-1. Y

For purposes of making small shipments of 1 lobsters as above described, the method of the invention may be adapted to sizeable containers for a considerable number of lobsters or to individual containers, with a single lobster in each.

Thus, as shown in Fig. 1, a carton having a cardboard body portion I, a metal bottom 2, an

open metal top rim 3, and a tight-fitting friction.

cover 4 may be used. The lobster may be placed in the-carton, withsufiicient sea water to cover it, as indicated at 5.

. A one-way gas valve 6 is previously fastened 20- through the bottom 2, as shown. The cover may now. be fitted in place on the body portion. Before and while the lobster is being. placed in the can, as well as thereafter, oxygen may be passed through the soft rubber valve 6 by connecting to any convenientsource of compressed oxygen gas as by inserting a needle l5 therethrough as shown in Fig. 4. The -cover is then. closed and sealed, and the oxygen continued long enough to develop the desired pressure. The source of oxy en is then withdrawn by retracting the needle l5, whereupon the valve 6 automatically closes and the package is hermetically sealed, ready for 'shipment. The carton may be made of water resistant material, such as waterproof cardboard or provided with an especially impenetrable liner 1 on the inside.

The valve 6 may be of any appropriate construction but conveniently is fashioned of soft rubber ,with a large mushroom head I'l, having a thin, soft, downwardly curved periphery l2 and a stem l3 which is passed (from the inside of the can) through a somewhat smaller hole in the tin bottom of the carton 2, provided to receive it.

The oxygen is introduced through a sharp, hollow needle I5 which is inserted through the stem and mushroom head and leads from a suitable supply of compressed oxygen (not shown) to deliver oxygen into the can uniformly andat such presthe inside of the can, thus effectively sealing it A tomarily used on paint cans.

against escape of the compressed oxygen or water in the container.

Another form of container suitable for larger numbers of lobsters, as shown in Fig. 2, may comprise a tin can 2| having a usual body portion 22 and a friction cover 23 suchas is cus- If more than one lobster is to be packed, they may be inserted back to back, or one on top of the other, as shown in Fig. 2, or a false bottom 24 of wire screening may be provided, standing somewhat above the bottom to provide a sump portion 25, in which solids and heavy matter may collect by sedimentation. Additional wire-trays or shelves 25 may be placed in the can to keep the lobsters apart, to advantage. In packing, the-lobsters are covered with sea water, which may already have been treated with oxygen, and oxygen then introduced through the one way gas valve 28 (similar to valve above described) passing through the bottom 21 and retained by a shoulder 30. The cover 23 is then I put in place and may be soldered as at 29. The

oxygen is continued so as to expel air through the hole 20, in the cover, which is then closed with a drop of solder. The introduction of oxygen is continued, to deliver the required amount or to develop the required pressure in the can, or both. The source of oxygen is then disconnected,

, by withdrawing the needle l5 as above described, and the one-way valve automatically closes against loss of oxygen or water, in the same manner, and the loaded can is ready for shipment.

A further form of container 3|, which is shown in Figs. 5-7, may be made of waxed Cellophane retains the contents of the container under pressure. The latter may then be conveniently carried, stored or shipped for considerable periods or other water-resistant transparent sheet material 32, rolled to form a hollow cylinder, and sealed along its joined edges 33 and then sealed and clamped at one end (by folding the material on itself at least twice), as at 34 and attaching a metal clamp 35, under pressure, with gripping projections 36, to hold it in place. The

container, thus formed may then be charged with I the lobster and enough water to cover it, throughthe open end 31. The sea water is preferably treated with oxygen either previously or while being arranged for and while packing the lobster or lobsters therein. The one-way valve 4 I, which is initially mounted in the Cellophane wall as shown in Fig. 6, serves for the introduction of oxygen under pressure.

The oxygen is introduced from a suitable source, through the valve 4|, which may in this instance be constructed and applied as above described or with the assistance of a concave disc of metal 42 wlth a hole 43 in the middle, through which the stem 44 is drawn and which grips the stem 44 against retraction and holds the mushroom rubber head 45 of the valve with its thin periphery-46, firmly and gas tight against the inside surface of the Cellophane, even though the latter may be very thin.

The open end 31 is then closed, as by rolling the edges together and clamped by a metal clamp similar to clamp 36, to hermetically close and seal this end, as with the end 34. When the air has preferably been first displaced by oxygen and a suflicient amount and/or pressure of oxygen has been provided (e. g., to keep the lobster or lobsters alive at least three days), after closing the end 3'l, the oxygen supply is disconnected by withdrawing the needle I5, through the thread-like hole 41, and thereupon the soft rubber of the valve around the thread-like hole 41 automatically closes behind it and hermetically seals and of time and for considerable distances. The particular advantage of the Cellophane container is, of course, that the lobster may be seen and inspected from time to time, without opening. The lobster might also be cooked without removing from the container and while still in the sea water, if desired. 7

As thus packaged and submerged in sea water, saturated with oxygen at least at a high concentration and preferably containing additional oxygen under appreciable pressure,e. g., substantially equivalent to that of the sea water in which the lobster has been accustomed to live,a lobster will not only remain alive for 7 to 10 days, but is found to .be actually healthier and livelier at the end of this time than when put into the container. Moreover, when used as a food, the meat of such a lobster is in many respects improved as toquality and flavor over that of a lobster as freshly caught. The physiological reasons why this is so need not be entered into, but it is an observed fact.

. It may alsov be observed that, while the invention has been described with particular reference to lobsters and the problem of keeping them alive,which is an especially diflicult problem and requires the provision of exacting care and conditions of treatment,-it may also be readily applied to the preservation of shell fish, such as clams, oysters, crabs and the like, to advantage.

1' claim:

1. Method of keeping lobsters alive, comprising the steps of putting a live lobster into a container with sufficient sea water completely to submerge its body, while passing oxygen into the container through the water, closing the container, continuing the introduction of oxygen to produce a concentrationv of oxygen greater than that of the atmosphere, and finally hermetically sealing the container.

2. Method of keeping lobsters alive, comprising the steps of puttinga live lobster into a container with sufilcient sea water completely to submerge its body, while passing oxygen into the container through the water, closing the container, continuing the introduction of oxygen to produce a concentration of oxygen greater than that of the atmosphere, and a pressure of 3 to 40 pounds per square inch above atmospheric pressure, and finally hermetically sealing the container.

3. Method of keeping lobsters alive, comprising the steps of putting a live lobster into a container with sufficient sea water completely to submerge its body, while passing oxygen into the container to displace the air therein, closing the container, continuing the introduction of oxygen into and through the water in the container, to

produce a pressure in the container substantially equivalent to, that of the sea water in whichlobsters usually live, and finally hermetically sealing the container.

4. Method of keeping lobsters alive, comprising the steps of putting a live lobster into a container with suflicient sea water, the oxygen content of which has been increased by preliminary contact with concentrated oxygen, to cover the under portion of the lobster, closing the container, introducing oxygen teproduce a concentrationof oxygen greater than that of the atmosphere, and hermetically sealing the container.

' JOSEPH R. MACDONALD. 

